The present inventive concept relates to a driving method of a nonvolatile memory device using a variable resistive element.
Examples of nonvolatile memory devices that use a resistance material include a phase change random access memory (PRAM), a resistive random access memory (RRAM), a magnetic RAM (MRAM), and the like. A dynamic RAM (DRAM) device or a flash memory device stores data by using an electric charge, while a nonvolatile memory device that uses the resistance material stores data by using a change in a state of a phase change material, such as a chalcogenide alloy, a change in resistance of a variable resistive material, and a change in resistance of a magnetic tunnel junction (MTJ) thin film due to a magnetization state of a ferromagnetic substance.
In the following description, a phase change memory is used as an example. The state of the phase change material is changed to a crystal state or an amorphous state while being cooled down after a heating process. Since the phase change material in the crystal state has low resistance, and the phase change material in the amorphous state has high resistance, the crystal state may for example be defined as set data or 0 data, and the amorphous state may for example be defined as reset data or 1 data.